Phytosterols for hair: what are the effects?

To prevent split ends and breakage, it is crucial to provide daily adequate hydration to your hair. Phytosterols can contribute to hair hydration due to their moisturising properties. Indeed, they have the ability to capture and retain water, and help to limit its evaporation.

Note : It is wise to remain cautious about the moisturising properties of phytosterols on hair. Indeed, these properties were first identified in skin and, so far, they have been very minimally studied in the haircare field.

The application of a treatment based on phytosterols to hair fibres could slow down the greying of hair due to the properties antioxidants of these compounds. Studies have indeed highlighted a link between oxidative stress and greying hair. Free radicals generated by UV rays, pollution or even tobacco degrade melanin, the pigment that gives hair its colour, via a series of reactions. It is also worth noting that free radicals are likely to weaken the hair bulb and promote hair loss and split ends.

Phytosterols protect hair from free radicals due to their chemical structure. This structure is rich in double bonds, which allows them to neutralise these reactive species through a donation of an electron. Furthermore, some studies suggest that phytosterols can stimulate the activity of endogenous antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase. These are essential proteins in the mechanism of eliminating free radicals.

It has recently been highlighted by a study conducted in vitro that β-sitosterol, a phytosterol found in the seeds of certain plants, could inhibit the growth of golden staphylococci, Gram-positive bacteria. However, the mechanism of action of β-sitosterol has not been determined. Even though further tests targeting other bacteria would be necessary, this study suggests that phytosterols could be useful in combating certain bacterial infections affecting the scalp.